Tower revolving crane



Feb. 15, 1955 H. LIEBHERR TOWER REVOLVING CRANE 2 Sheets-Sheet 1 Filed NOV. 8 1950 Fig.7

IN VEN 7'0 12 HRIVS /EB//RR Feb. 15, 1955 H; LIEBHERR 2,702,129

' TOWER REVOLVING CRANE FiledrNov. 8. 1950 2 Sheets-Sheet 2 i 5 IN V EN TOR.

United States Patent 6 2,702,129 TOWER REVOLVING CRC-ANE Hans' Liebhe rr, Kirchdbrf, Germany Application Novena s, 1950; semi No. 194,607

('llaimspriority,.application Germany November'10,'.1949

The inventioifconcerns a' revolving tower crane and has'i'as' its object to provide; means leading. toa highly efficacious; and simplified construction.

Inknowmtowercranes of the" revolving type; the turn-- ing column protrudes into the undercarriage and carries at its lowerend a step bearing.-

In order to; secure per-feet stability,.- the flange ring and the runners of' such bearing arrangement must be arranged at aisuflicient. distance. above such step bearing, 'eby, however,. the possibilities of fixing and displaci'ng the service platform for the crane operator; are lir'nit'edi Eora complete. survey of the range of operationof the-fcra'n'eit is useful. tomount the 1 service platform. on the turning column, so that the platform will revolve together with the column.

With revolving. tower cranes" it: is common to use as stpbe'arin'gs an. insertpiece between: compressive seats. Ins'e'rt arid. seats are. held together-l by a guide? b'olt. In order to avoid binding, the stable guide bolt passes into the turntable seat through a socket.

According to the invention, this step bearing is simplified by the elimination of the socket, the insert being guided relative to a seat with relatively .small play. Arranged like this, the seat takes over the lateral guidance of the turning column at the step bearing, whereas the guide bolt passes freely through the bearing seat and absorbs only vertical stresses.

Besides the guide socket, the guide bolt mayalso be dispensed with, if according to another feature of the invention the insert is curved to such an extent that the step bearing absorbs completely the lateral stresses upon the crane.

A preferred form of such curved insert is hemispherical or is shaped as a segment of a sphere of sufficient height.

Other features, objects and advantages of the invention will ensue from the following disclosure and description of the invention, the claims hereto attached and the drawings in which:

Fig. 1 represents the lower part of a revolving tower crane, shown schematically and in elevation;

Fig. 2 is a sectional view through the bearing employed in the invention and used in the embodiment of Fig. 1;

Fig. 3 represents another embodiment of a bearing, shown in section and usable in connection with the crane shown in Fig. 1;

Fig. 4 shows a crane according to the invention in elevation and in operative condition;

Fig. 5 illustrates partly in section and in elevation the lower part of the column of the crane seen in Figs. 1 and 4 with further details of drive means therefor;

Fig. 6 is a top plan view of Fig. 5, partly shown in section.

Referring now more particularly to the drawings, there is disclosed a track 1 on which moves a carriage 4 with pairs of rollers or wheels 2 and 3. A flange-shaped piece 5 with an outer toothed rim 6 is fixed on said carriage and has an inner smooth running surface 7. Also fixedly attached to carriage 4 and centrally arranged with re spect to flange 5 is a carrier 8, which may be, as shown, in the form of a truncated pyramid. Carriage 4 and carrier 8 form together the undercarriage of the revolvable crane.

A turning column 9 is centered with respect to flange 5 and carrier 8. At the level of the running surface 7 of flange 5, the column 9 with its supporting base por- 7, 2,702,129 Patented Feb. 15, 1955 ice and 6) which; roll: along surface-'7 during: rotation'i. ofcolumn 9.. The eccentric. mounting of r the; bolts: usually: employed for runners: is: utilized-to adjust the-rollers 10;. so? as to. be free from playagainst saidsurface 7;

Above flange 5: theturning. column 9; 9a.;carries plate form 11, on which drivemeans for. thezlifting andrturne' ing gearingis supported. Drivenpby motor: M: and: suit-- able transmission: means T a: pinion. 6a: meshes with: toothed rim 6, so that the turning; platform; 11-: andvree volving: column 9 withwbase: support 911' turn about the:

. verticalaxisof carrier 8; Drive-and transmission means? tion 9a carries four runners or guide rolls 10 (Figs. 1

(not shown) may. be'furthen providedrif desired coupled; witlr motor M1 to actuate rollers 2; 3' forrmoving same: along: track 1.v

While the rolls 10 guide the column laterallyrstepi bearing 12 supports column 9' on the.- undercarriage; According to- Fig. 2' the step: bearing; 12': comprises two seats213 14 with an; insert: piece. 15, therebetweeni; Seat? 13' is mounted on.- and" let: in the top of carrier- 8, as: shown, while seat 1'4"is held. between two double angle; iron members- 16', 17, which are welded to-and 'between double angle i'ronmembers 18 of column 9;

The aforesaid" insert. piece- 15' is held freerfrorrr play and isnot movable in" regard: to arecess in: seat .13. Flange 19 depending'from; seat 14 protrudesai predetere mined: distanceover A the lateral: wall: of insertipie'ce. 15, so: that an annular space: 20' is formed," which facilitates l'a'teral: play: between: insert 15 and: seats.14.: In" spitezofi suitable guidanceof runners: or rolls 10 alongflang'e 5,: seat-1'4 must offer a predetermined: lateral mobility; 1161a: t'iveto seat 13., asatheelasti'city of'th'e-steel; usedas build ing'mater ial forthe crane, r'esultsina;constructionzwhicha is'not absolutelyrigid; Due= tosmall possible deformae tionsi caused by" the: change. of: loading; on unloadingiofi the beamz of: the craner and due"; totthei respective; posi tion of the turning column, a certain lateral give of the revolving column 9 adjacent the undercarriage is sometimes necessitated. This is taken care of by the mentioned play between seat 14 and insert piece 15 at 20.

These small lateral movements of the turning column are limited by the contact of the depending flange part 19 with the cylindrical surface 21 of said insert.

A guide bolt 22 mounted at 22a to the undercarriage 4 protrudes through a perforation or bore passing through the step bearing. This guide bolt 22 has thus a sufiiciently large play in order to facilitate lateral movements of column 9 in regard to insert 15 and seat 14.

The aforesaid bolt 22 and a nut 23 secure the step bearing parts together. As is conventional, guide bolt 22 may have bores to allow accommodations therein of electric cables and other accessories (not shown).

In the step bearing heretofore used, the insert was freely movable relative to its two seats and the guide bolt was free from play and guided through a socket. Accordingly, the invention dispenses with this socket arrangement and flange 19 of seat 14 surrounds the upper part of insert 15 thereby providing an annular space 20 therebetween and thus forming lateral guide means adjacent step bearing 12 for the turning column 9.

In the embodiment of Fig. 3 the insert 24 is ball-shaped and sandwiched between seat 25 and seat 26. The disposition and mounting of seat 25, 26, on the under carriage and turning column corresponds otherwise to the manner indicated hereinabove with respect to Fig. 2.

Ball-shaped element 24 is sharply curved so that lateral forces cannot shift or separate the parts of which this bearing consists. The guide bolt in this particular embodiment may be eliminated.

Instead of a complete spherical body or element a sufiiciently large spherically shaped element with sharp curvature may also be employed, so that the step bearing will always fully absorb lateral forces or stresses exerted on the crane.

In order to facilitate the necessary reciprocal movements seats 13, 14 and 25, 26 are arranged so as to create relatively small gaps 27, 28 therebetween. Any suitable known means may be provided for lubricating step bearing 12.

Fig. 4 shows the tower crane with its turning column in complete operative position. Motor M and transmission means T with suitable reduction gearing drive platform 11 about and above carriage 4 and along fixed flange ring 5, while the column 9 is guided at 10 and 7 in desired manner.

It can thus be seen that there has been provided according to the' invention a revolving tower crane of the character described, which comprises an undercarriage, a carrier projecting upwardly from said undercarriage and secured thereto, an upright turning column arranged concentrically with respect to said carrier, bearing means interconnecting the upper end of said carrier and said turning column at a level spaced above the lower end of said turning column, respective rollers and circular track means for engagement with said rollers and disposed adjacent the lower end of said turning column for maintaining said turning column against lateral displacement during rotation thereof, said rollers being arranged in spaced apart relation to engage said track means at equal intervals thereabout, and platform means positioned above said undercarriage and connected to said turning column for rotation therewith.

It is to be understood that minor changes and variations inthe construction, shape and position of the parts of the crane may be had without departing from the spirit, scope and fundamental concept on which the invention is based and as pointed out in the claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent, is: 1. A crane structure comprising an undercarriage, a carrier projecting upwardly from said undercarriage and secured thereto, an upright turning column arranged concentrically with respect to said carrier, bearing means interconnecting the upper end of said carrier and said turning column at a level spaced above the lower end of said turning column, respective rollers and circular track means for engagement with said rollers and disposed adjacent the lower end of said turning column for maintaining said turning column against lateral displacement during rotation thereof, said rollers being arranged in spaced apart relation to engage said track means at equal intervals thereabout, and platform means positioned above said undercarriage and connected to said turning column for rotation-therewith.

2. A crane structure according to claim 1, wherein said bearing means includes respective members carried by said carrier and said turning column and cooperating to define opposed seats therebetween, an immovable insert interposed between said carrier and said turning column and mounted between said opposed seats, and means operatively interconnecting said members and said insert, one of said bearing members being rotatable with respect to the other of said bearing members.

3. A crane structure according to claim 1, wherein said bearing means includes respective members on said carrier and said turning column, said members cooperating to define at least one spherical seat, and a fixed insert shaped complementary to said spherical seat and mounted therein.

4. A crane structure according to claim 2, wherein said insert is provided with a central perforation, said interconnecting means including a fastener element traversing said seats and said perforation of said insert.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain Jan. 21, 

